Marine steering and propulsion device

ABSTRACT

A marine steering and propulsion device comprising a hollow jet cylinder having vanes provided on and extending horizontally and outwardly from the outer periphery in the diametrically opposite directions, a rotary turbine casing journalled in said jet cylinder and having a bevel gear extending about the outer periphery of said turbine casing, a Kaplan turbine received within said turbine casing for rotation with the casing with the axis of said turbine intersecting the vertical center line of said jet cylinder, a lower jet cylinder support mounted in the lower portion of the stern of a ship body for rotatably supporting the lower end of said jet cylinder, an upper jet cylinder support including a propulsion shaft extending into the upper portion of said jet cylinder and having at the lower end a lower bevel gear in meshing with said bevel gear on the turbine and an upper bevel gear drivingly connected to propulsion drive secured to the upper portion of said stern of the ship body and a worm wheel journalled on said propulsion shaft below said upper bevel gear and drivingly connected to steering drive.

United States Patent Shima 5] Nov. 11, 1975 MARINE STEERING AND PROPULSION DEVICE [57] ABSTRACT [76] Inventor: Kiyoshi Shima, 14-2 Tsujido A marine steering and propulsion device comprising a Shin-Machi l-Chome, Fujisawa, hollow jet cylinder having vanes provided on and ex- Kanagawa, Ja an tendin horizontall and outwardl from the outer ev rip cry in t e lametrlca y opposite irectlons, a ro- [22] 1974 tary turbine casing journalled in said jet cylinder and [21] Appl. No.: 527,504 having a bevel gear extending about the outer periphcry of said turbine easing, a Kaplan turbine received 7 7 within said turbine casing for rotation with the casing 7 Cl 133 with the axis of said turbine intersecting the vertical [51] Int Cl 2 B63 1/12 B63H 55/04 center line of said jet cylinder, a lower jet cylinder [58] Fieid earch l 15/34 B 35 l 6 12 R. support mounted in the lower portion of the stern of a hi bod for rotatabl su rtin the lower end of l 14/151 60/31 74/457 459's said et cylinder, an upper et cylinder support including a propulsion shaft extending into the upper portion [56] References cued of said jet cylinder and having at the lower end a UNITED STATES PATENTS lower bevel gear in meshing with said bevel gear on 2.446.229 8/1948 House /42 the turbine and an upper bevel gear drivingly con- 2.795.201 6/1957 Fogarty et a1... nected to propulsion drive secured to the upper por- 2,997.0l5 RIChteI' B tion of tern of the body and a worm whee] journalled on said propulsion shaft below said upper bevel gear and drivingly connected to steering drive.

2 Claims, 5 Drawing Figures Sheet 1 of 3 US. Patent Nov. 11,1975 Sheet2of3 3,918,389

US. Patent Nov. 11, 1975 Sheet 3 013 3,918,389

MARINE STEERING AND PROPULSION DEVICE Background of the Invention This invention relates to a marine steering and propulsion device and more particularly, to a marine steering and propulsion device of the type which comprises a jet cylinder having horizontal vanes on and extending from the outer periphery of said jet cylinder in the diametrically opposite directions, a bearing casing mounted on the upper portion of the stern of a ship body for journalling the upper portion of said jet cylinder, a lower bearing means mounted in the lower portion of said stern of the ship body for journalling the lower portion of said jet cylinder and a turbine casing journalled in said jet cylinder for rotation therein and having a Kaplan turbine received in said turbine casing for rotation with the casing.

There have been proposed and practically employed a number of marine steering and propulsion devices and in one representative conventional steering and propulsion device, the rotational drive force from an outboard motor is transmitted through a bevel gear at the upper end of a vertical propulsion shaft to the propulsion shaft and the thus transmitted rotational drive force is then transmitted through a bevel gear at the lower end of the propulsion and a bevel gear having substantially the same diameter as the gear at the lower end of the propulsion shaft and secured to the propeller shaft to the propeller to thereby rotate the propeller on the propeller shaft. Therefore, the rotation torque to be transmitted to the propeller shaft is small. Thus, the conventional marine steering and propulsion device applies an excessive force on the propeller shaft which is required to provide a great propulsion load resulting in reduction of operation efficiency and leading to failure.

Summary of the Invention Therefore, the present invention is to provide a novel and improved marine steering and propulsion device which can effectively eliminate the disadvantages inherent in the conventional steering and propulsion devices.

The steering and propulsion device of the present invention generally comprises a hollow jet cylinder journalled between a bearing casing supported on support means secued to the upper portion of the stern of a ship body and bearing means secured to the lower portion of the stern, a rotary turbine casing journalled in the jet cylinder and having a larger bevel gear provided about the outer periphery of the turbine casing, a Kaplan turbine provided within the turbine casing for rotation together with a turbine casing, a vertical propulsion shaft having the lower end portion extending into the jet cylinder and provided at the extremely lower end with a smaller bevel gear in meshing with the larger bevel gear and at the extremely upper end with a bevel gear drivingly connected to a drive shaft extending from the upper portion of the ship body stern whereby the rotational drive force from a drive mechanism provided in the ship body is transmitted through the propulsion shaft drive shaft and the bevel gear at the upper end of the propulsion shaft to the propulsion shaft which in turn drives the larger bevel gear on the turbine casing through the bevel gear at the lower end of the propulsion shaft to thereby rotate the turbine casing resulting in the rotation of the turbine. As the Kaplan turbine is rotated in the manner mentioned hereinabove, propulsion jets are sent out of the jet cylinder. For the purpose of steering, a worm wheel is journalled in the bearing casing in a position below the upper end bevel gear on the propulsion shaft and a worm is in meshing with the worm wheel to be driven by motor means whereby when the motor means is energized, the motor means rotates the worm which in turn rotates the worm wheel. The rotating worm wheel in turn rotates the jet cylinder through the propulsion shaft in one or the other direction so as to effect any desired steering operation.

According to the present invention, the rotation of the Kaplan turbine is utilized for steering and the rotation torque of the propulsion shaft is augmented by means of the larger bevel gear on the turbine casing.

The larger bevel gear on the turbine casing should be a strong and large gear sufficient to stand against an expected high load while the ship is being propelled. In order to meet the requirement, the larger bevel gear is in the form of an annular metal disc having one surface in which a plurality of equally spaced tooth receiving grooves which extend radially and the disc reduces its thickness from the outer periphery toward the inner periphery of the disc to provide an inclination to the surface. Inserting teeth are snugly inserted in the grooves respectively. Each of the tooth receiving grooves is provided in the center with a through hole which intersects the groove at right angle and which increases the diameter from the grooved surface to the other surface of the disc. Each of the inserting teeth has a reduced width base portion snugly received in the associated groove and a partially threaded bar extends from the bottom of the base portion of the associated inserting tooth. A split collar is disposed within the center hole in each of the grooves about the partially threaded bar and a nut is threaded on the threaded portion of the associated bar to firmly hold the bar in position.

With the above construction of the larger bevel gear on the turbine casing, the bevel gear can be easily produced and when one or more of the teeth have been worn or damaged, it is necessary that only the worn or damaged teeth are replaced by new teeth to thereby eliminate the necessity for the replacement of the entire bevel gear which was otherwise necessary for the conventional bevel gears employed in the like marine steering and propulsion devices.

According to the present invention there has been provided a marine steering and propulsion device which comprises a hollow jet cylinder having horizontal vanes provided on and extending outwardly from the diametrically opposite positions of the outer periphery of said cylinder in the opposite directions, a rotary turbine casing journalled in said jet casing and having a larger bevel gear extending about the outer periphery of said turbine casing for rotation together with the easing with the axis of the turbine intersecting the vertical center line of said jet cylinder at right angles, upper and lower bearing means for rotatably supporting said jet cylinder and a vertical propulsion shaft extending through said upper bearing means into said jet cylinder and having at the lower end a smaller bevel gear in meshing with said larger bevel gear on the turbine casing whereby the rotation of said propulsion shaft rotates said Kaplan turbine within said jet cylinder to provide propulsion jets.

The above and other objects and attendant advantages of the present invention will be more readily apparent to those skilled in the art from a reading of the following detailed description in conjunction with the 3 accompanying drawings which show one preferred embodiment of the invention for illustration purpose only, but not for limiting the scope of the same in any way.

Brief Description of the Drawings FIG. 1 is a front elcvational view of one preferred embodiment of marine steering and propulsion device constructed in accordance with the present invention;

FIG. 2 is a side elevational view in partial section of said marine steering and propulsion device as shown in FIG. 1;

FIG. 3 is a fragmentary perspective view on an enlarged scale of portion of the larger bevel gear of the turbine casing as shown in FIG. 2;

FIG. 4 is a cross-sectional view taken along substantially the line IVIV of FIG. 3; and

FIG. 5 is an exploded perspective view of the larger bevel gear.

Preferred Embodiment of the Invention The present invention will now be described referring to the accompanying drawings, and more particularly, to FIGS. 1 and 2 thereof which show one preferred embodiment of marine steering and propulsion device of the invention for illustration purpose only. The marine steering and propulsion device generally comprises a hollow cylindrical turbine casing l of a circular crosssection as seen in elevation and having a Kaplan tur bine 2 received therein for rotation with the casing. The turbine casing l is journalled in a substantially circular jet cylinder 3 by means of upper and lower bearings 4 and 5. The turbine casing 1 is provided in its outer periphery with a larger bevel gear 6 which is freely received for rotation in an annular recess 7 formed in the inner periphery 3 of the injection cylin der 3. Horizontal underwater vanes 8 are provided on and extend the outer periphery of the jet 3 in the opposite directions. The jet cylinder 3 is provided in the upper portion thereof with an integral hollow mounting portion 3a which tapers upwardly and a propulsion shaft 9 extends vertically through the hollow interior of the mounting portion 3a. The lower end portion of the propulsion shaft 9 is provided at the lower end with a smaller bevel gear 10 which is in meshing with the larger bevel gear 6 on the Kaplan turbine casing 1 and the propulsion shaft is journalled in a position above the bevel gear 10 by means of bearings 11 which are in turn mounted within the hollow interior of the jet cylinder mounting portion 3a. A hollow cylindrical member 12 is supported on the mounting portion 3a of the jet cylinder 3 with the bottom annular flange 12a of the cylindrical member seating on the top of the mounting portion 3a. The propulsion shaft 9 is provided at the upper end with a bevel gear 13 having the same diameter as the bevel gear 10 and a worm wheel 14 is journalled on the propulsion shaft 9 in a position below the bevel gear 13 by means of bearings 15. The worm wheel 14 is secured to the cylindrical member 12 by means of set screws 16 and in meshing with a worm 17 which is in turn connected to steering means (not shown) to be driven by the worm. A frusto-conical bearing casin g 18 is provided about the hollow cylindrical member 12 and has an upper shoulder 18 against which the worm gear 14 abuts and a lower shoulder 18 against which the flange 12a of the hollow cylindrical member 12 abuts. The bearing casing 18 is connected through a connecting member 19 to the upper portion 20 of the ship body. A drive shaft 21 which is driven from power source within the ship body (not shown) extends rearwardly from the stern of the ship body and is provided at the outer or rear end with a bevel gear 22 which is in meshing with the bevel gear 13 to transmit driving force through the latter gear to the propulsion shaft 9. A lower jet cylinder support shaft 23 extends downwardly from the bottom of the jet cylinder 3 and is journalled in the lower portion of the stern of the ship body. Thus, the jet cylinder 3 rotates about its vertical center line. Numeral 24 denotes steering motors for steering the jet cylinder and in consequence, the turbine casing and the motors are rotated in the opposite directions.

Referring now to FIGS. 3 through 5 in which one portion of the larger bevel gear 6 on the jet cylinder is shown in an enlarged scale. The main body 25 of the larger bevel gear 6 is formed of an annular metal disc and one surface (the upper surface as shown in FIGS. 3 through 5) slopes downwardly toward the inner periphery of the disc and is provided with a plurality of equally spaced tooth receiving grooves 26 extending radially. Inserting teeth 27 are received in the radial tooth receiving grooves 26 by means of the reduced width bottoms 27a of the teeth. Each of the tooth receiving grooves 26 is provided in the center with a frusto-conical through hole 260 which increases its diameter downwardly and intersects the groove at right angles for receiving the bar 28 projecting from the bottom of the associated inserting tooth 27. The bar 28 is provided in the lower end portion with threads. A split frusto-conical collar 29 is provided within the associated center hole 26a about the bar 28 of the associated inserting tooth 27 and a nut 30 is threaded on the threaded lower end of the bar 28 to firmly hold the bottom 27a of the inserting tooth 27 in position within the groove 26. For the purpose, the underside of the main body 25 is recessed at 26b in positions surrounding the center holes 26a to define shoulders against which the nuts 30 abut. As well known in the art, the nuts 30 are tightened to firmly apply the collars 29 against the bars 28 to hold the inserting teeth 27 in position. The inserting teeth 27 have been formed of any conventional material for gear teeth and heat-treated.

The operation of the marine steering and propulsion device of the invention is thought to be apparent from the foregoing description, and therefore, a detailed description of the operation is not thought necessary.

While only one embodiment of the invention has been shown and described in detail, it will be understood that the same is for illustration purpose only and not to be taken as a definition of the invention, reference being had for the purpose to the appended claims.

What is claimed is:

1. A marine steering and propulsion device comprising a hollow jet cylinder having horizontal vanesprovided on and extending outwardly from the diametrically opposite positions of the outer periphery of said cylinder in the opposite directions, a rotary turbine casing journalled in said jet casing and having a larger bevel gear extending about the outer periphery of said turbine casing, a Kaplan turbine received within said turbine casing for rotation together with the casing with the axis of the turbine intersecting the vertical center line of said jet cylinder at right angles, upper and lower bearing means for rotatably supporting said jet cylinder and a vertical propulsion shaft extending through said upper bearing into said jet cylinder and having at the lower end a smaller bevel gear in meshing with said 2. The marine steering and propulsion device as set forth in claim 1, in which said grooves have a through hole which increases in width from said grooved surface to the other surface of said disc, said inserting teeth have partially threaded bars extending from the bottoms thereof into said through holes, frusto-conical split collars are disposed within said through holes about said partially threaded bars and nuts are threaded on the bars to hold the inserting teeth in position within the grooves. 

1. A marine steering and propulsion device comprising a hollow jet cylinder having horizontal vanes provided on and extending outwardly from the diametrically opposite positions of the outer periphery of said cylinder in the opposite directions, a rotary turbine casing journalled in said jet casing and having a larger bevel gear extending about the outer periphery of said turbine casing, a Kaplan turbine received within said turbine casing for rotation together with the casing with the axis of the turbine intersecting the vertical center line of said jet cylinder at right angles, upper and lower bearing means for rotatably supporting said jet cylinder and a vertical propulsion shaft extending through said upper bearing into said jet cylinder and having at the lower end a smaller bevel gear in meshing with said larger bevel gear on the turbine casing whereby the rotation of said propulsion shaft rotates said Kaplan turbine within said jet cylinder to provide propulsion jets, the said largeR bevel gear on the turbine casing comprises an annular metal disc which has one surface sloping downwardly from the outer periphery to the inner periphery and provided with a plurality of equally spaced grooves extending radially and inserting teeth received in said grooves.
 2. The marine steering and propulsion device as set forth in claim 1, in which said grooves have a through hole which increases in width from said grooved surface to the other surface of said disc, said inserting teeth have partially threaded bars extending from the bottoms thereof into said through holes, frusto-conical split collars are disposed within said through holes about said partially threaded bars and nuts are threaded on the bars to hold the inserting teeth in position within the grooves. 